More than 40 factors affecting the development of hypertension are known. They can be acquired or congenital. Hereditary factors are most often:
- arteriovenous fistula;
- fibromuscular anomaly and renal artery aneurysm;
- hypoplasia of the kidney and its artery;
- extravasal compression of the artery of the kidney.
Acquired factors for the occurrence of CVH include:
- stratified aortic aneurysm;
- aortoarteritis (non-specific);
- k >Atherosclerosis is the main cause of the appearance of vasorenal hypertension in patients who are over 40 years old. In this case, the disease develops in 60-85% of people. At the same time, atherosclerotic plaques are collected in the proximal third of the artery or the mouth of the kidney.
In most cases, the lesion is unilateral, and bilateral occurs in approximately 1/3 of the cases, due to which the course of the disease becomes more severe.
The left and right arteries are affected at the same frequency. In 10% of cases, atherosclerosis is complicated by thrombosis. Moreover, the disease is 2-3 times more likely to develop in men.
Musculoskeletal dysplasia is a secondary cause after atherosclerosis. Such an anomaly is often observed between the ages of 12 – 44 years, and the average age of the disease is 28-29 years. It is noteworthy that in women, PMD occurs 4-5 times more often than in men.
This condition is characterized by sclerosing and dystrophic changes in the middle and inner shell of the renal arteries and their branches. Moreover, muscle hyperplasia is often combined with microaneurysms. As a result, narrowed and widened areas appear, due to which the arteries in shape become similar to beads.
Nonspecific aortoarteritis is the third cause of CVH (10%), which manifests itself as a primary lesion of the middle membrane of the vessel. In this condition, the aorta is affected with varying degrees
Also, CVH can occur against the background of extravasal compression of the artery due to embolism or thrombosis, abnormalities in the development of the kidneys, nephroptosis, cysts, and so on.
How does vasorenal hypertension develop?
Occlusion or narrowing of the renal artery helps to reduce perfusion pressure and blood flow. This leads to poor elasticity of the leading arterioles of the malpighian glomerulus.
The granular cells of JGA located in the medial layer are very sensitive to changes in renal hemodynamics, they secrete incretrenin in the blood. The appearance of renal tissue ischemia contributes to the hyperplasia of Juga cells, due to which hypersecretion of renin develops.
Renin is an enzyme that converts angiotensinogen into angiotensin I, passing angiotensin II. He is a strong vasoconstrictor, cramping systemic arterioles, resulting in increased peripheral resistance.
Also, angiotensin II contributes to the production of aldosterone, which is why secondary hyperaldosteronism develops with the retention of water and sodium in the body. This contributes to swelling and increased peripheral resistance.
For the occurrence of atherosclerotic vasorenal hypertension, a decrease in renal blood flow is characteristic. This condition ends with ischemic nephropathy (an absolute loss of organ performance).
So, fibromuscular dysplasia, as a rule, occurs in young women. Its course is not progressive, therefore, ischemic nephropathy develops extremely rarely.
There are no pathognomonic manifestations of CVH, which are characteristic of certain forms of arterial hypertension (pheochromocytoma, Conn’s syndrome, etc.). But some manifestations contribute to this disease:
- Inherent to cerebral hypertension – insomnia, pain in the head and eyeballs, noise in the shah, memory impairment.
- Arising as a result of coronary insufficiency and overload of the left parts of the heart – a feeling of heaviness behind the sternum, a frequent heartbeat, heart pain.
- Characteristic for the syndrome of a systemic inflammatory reaction (nonspecific aortoarteritis);
- Heaviness in the lower back, hematuria (heart attack of the kidney), mild pain.
- The characteristic features of secondary hyperaldosteronism are nocturia, muscle weakness, polydipsia, paresthesias, polydipsia, tetany attacks, polyuria, isohypostenuria.
- Caused by ischemia of other organs – the main arteries are affected along with the vessels of the kidneys.
In addition, it should be noted that in about 25% of patients, vasorenal hypertension occurs without manifestations.
To diagnose CVH, it is important to take into account various medical data:
- The relationship of the onset of hypertension with childbirth and pregnancy.
- Increased pressure at a young age.
- The appearance of hypertension after hematuria with heart disease or arrhythmia, or in patients with episodes of embolism and post-infarction cardiosclerosis.
- Reflexivity to hypertension therapy after 40 years, when the disease was previously benign, and treatment effective. Determination in such patients of intermittent claudication or manifestations of cerebrovascular insufficiency (chronic).
During the examination, pressure is measured on the arms and legs, due to which coarctation syndrome is excluded. It also allows you to see lesions of the limbs.
In this case, a vertical and horizontal measurement is made. So, when in the orthostatic position, blood pressure is higher, then there are suspicions of nephroptosis.
Auscultation of the renal arteries and abdominal aorta is still being performed. Approximately half of the patients heard systolic murmur in the projection of the abdominal and renal arteries.
In addition, if necessary, systolic murmur is heard over arteries located superficially (femoral, subclavian, carotid). Such changes indicate a systemic lesion in aortitis and atherosclerosis.
Relying on research data, medical history and examination results, characteristic symptoms are revealed that indicate the presence of vasorenal hypertension. These include various sizes of the kidneys (ultrasound) and hypertension resistant to several diuretics and blood pressure lowering drugs.
Also, the development of the disease is indicated by rapidly progressing or malignant hypertension, systolic murmur over the renal arteries and the abdominal aorta and the occurrence of hypertension in women under 20 years old and in men over 55 years old. Even vasorenal hypertension often appears against the background of azotemia, which develops as a result of treatment with angiotensin II receptor blockers, ACE inhibitors and the presence of various symptoms of atherosclerotic disease.
However, these factors can only suspect the occurrence of CVH. Therefore, additional studies are conducted to confirm or exclude the disease.
The most informative way to diagnose vasorenal hypertension is considered angiography. This procedure is performed in the vascular centers, with its help it is possible to identify factors of the development of the stenotic process, to assess the localization and degree of stenosis.
Moreover, screening and minimally invasive studies are used to help see damage to the renal arteries and establish indications in angiography or to avoid it with a different genesis of hypertension.
Thus, high sensitivity is observed with CT angiography, renal scintigraphy using ACE inhibitors, magnetic resonance angiography and duplex scanning. They are combined or used separately, which allows for adequate screening prior to radiopaque angiography.
The use of ACE inhibitors in stenosis of the arteries of the kidneys helps to reduce glomerular filtration rate due to the elimination or weakening of the constriction of efferent areoles. As a result, changes in the renogram are noted, and “medicamentous nephrectomy” is found on the affected side of the artery, which indicates a violation of the main renal blood flow.
A reduced, poorly functioning kidney and symmetrical bilateral disorders burn about the average likelihood of vasorenal hypertension.
Also, for the diagnosis of CVH, duplex scanning is performed. In this case, 2 methods for determining the disease are used:
- analysis of Doppler waveforms;
- direct visualization of the renal arteries.
Direct visualization involves ultrasound examination with an analysis of blood flow velocity and energy or color Doppler examination.
Using three-dimensional ultrasound angiography, renal arteries can be visualized. The image accuracy of this diagnostic procedure is comparable to a three-dimensional MPA.
For ultrasound diagnosis of occlusion or proximal stenosis, the following criteria apply:
- increase in the highest systolic speed;
- the renal-aortic coefficient of the highest speed is more than 3, 5;
- visual observation of the renal artery without detecting the Doppler signal, which indicates occlusion;
- turbulent flow in the post-stenotic zone.
Even thanks to an ultrasound examination, indirect symptoms of vasorenal hypertension can be determined – a decrease in kidneys due to ischemic atrophy. Kidneys whose length is less than 8 cm are often damaged by ischemia. In this case, revascularization does not restore function and does not localize hypertension, therefore, in this case, nephrectomy is performed.
In addition, to diagnose CVH, magnetic resonance angiography with contrast Gadolinium is performed, providing a high-quality three-dimensional image. So, motionless tissues look like dark places, and the blood remains bright.
Spiral computed tomographic angiography is also performed, which is a non-invasive method in which a contrast agent is administered intravenously. It is worth noting that this method also allows you to get a three-dimensional image of blood vessels.
In the absence of therapy, approximately 70% of patients die from vasorenal hypertension within five years, due to complications of systemic hypertension. These include renal failure, myocardial infarction, and cerebral stroke.
Conservative treatment of CVH in most cases is not very effective, therefore its effect is short-term and intermittent. Therefore, even with a decrease in blood pressure, with renal artery stenosis, the blood supply is disturbed even more. This leads to secondary wrinkling of the kidney with a loss of its function.
Long-term drug treatment is advisable only if it is impossible to perform the operation, or it can be an addition to surgery if it did not help reduce the pressure to the required numbers.
The leading therapeutic methods for vasorenal hypertension are surgery and endovascular dilatation. Indications for renal artery RED are monofocal stenosis of the arteries, if fibro-muscular dysplasia, stenosis of segmental branches and narrowing of the proximal segment occur.
Indications for surgery are a confirmed diagnosis – vasorenal hypertension, if there is no possibility to perform stenting and RED, or at their low efficiency.
In the presence of vasorenal hypertension, the following types of open surgery are performed:
- conditionally reconstructive;
- reconstructive surgery.
If there is occlusion or narrowing of the renal artery, an operation is performed, the main purpose of which is to resume the main blood flow in the kidneys.
Contraindications to surgical intervention are:
- wrinkling of both kidneys;
- severe heart failure;
- severe coronary and cerebral circulation disorders.
In approximately 35% of patients suffering from VRH, bilateral narrowing of the arteries of the kidneys is detected. If the lesions are hemodynamically equivalent, then a series of operations are performed with a frequency of 3-6 months.
Simultaneous reconstruction of the renal arteries is used in case of multiple stenosis of the arteries or in aortitis, if the visceral and renal arteries are reconstructed.
When the degree of lesion is unequal, blood flow is initially restored at the site of the largest lesion. For patients with a shrunken kidney and hemodynamically significant stenosis, blood flow in the narrowing area is resumed at the beginning, and then, after 3-6 months, nephrectomy is done.
Often along with the kidneys, the brachiocephalic arteries are affected. In this case, the priority of revascularization is determined depending on the effect after artificial hypotension.
Regarding surgical access, it is possible to get to the renal artery through thoracophrenolumbotomy and upper or median transverse laparotomy. But often the choice falls on a thoracophrenolumbotomy, which allows you to create good conditions for any type of reconstruction.
In addition, this technique gives the maximum angle of surgical action and the minimum depth of the surgical wound. It is these advantages that make thoracophrenolumbotomy an optimal choice for vasorenal renal hypertension.
The video in this article will clearly demonstrate what renal hypertension is and why it is dangerous.
Detonic – a unique medicine that helps fight hypertension at all stages of its development.
The complex effect of plant components of the drug Detonic on the walls of blood vessels and the autonomic nervous system contribute to a rapid decrease in blood pressure. In addition, this drug prevents the development of atherosclerosis, thanks to the unique components that are involved in the synthesis of lecithin, an amino acid that regulates cholesterol metabolism and prevents the formation of atherosclerotic plaques.
Detonic not addictive and withdrawal syndrome, since all components of the product are natural.
Detailed information about Detonic is located on the manufacturer’s page.